150 Years of Hardy Plants

Shrubs

WHEN TO PRUNE small trees and shrubs depends on when they flower. Plants grown primarily for early spring flowers (on the previous year's growth) should be pruned immediately after they finish blooming. This includes azaleas, forsythias, pearl bush, flowering plums, crabapples, and redbuds. Fruit trees are best pruned in late winter, before they begin new growth.

Shrubs grown primarily for their foliage, rather than showy flowers, should be pruned in spring before growth begins. This includes dogwood, honeysuckle, barberry, alpine current, purpleleaf sandcherry, smokebush, and buffaloberry.

Shrubs that bloom on new growth may be pruned in spring before growth begins. Plants with marginally hardy stems such as clematis and shrub roses should be pruned back to live wood. Hardier shrubs such as late blooming spireas and smooth (snowball) hydrangeas should be pruned to the first pair of buds above the ground.

PRUNE OLDER or overgrown shrubs every year by removing up to one-third of the oldest, thickest stems or trunks, taking them down to the ground. This will encourage the growth of new stems from the roots. Once there are no longer any thick, overgrown trunks left, switch to standard pruning as needed.

'Isanti' is a slower growing selection of native dogwood. 'Cardinal' was introduced for its vivid red winter twig color. Both grow well in full sun or partial shade and tolerate poorly drained soils.

'Northern Pearls' is the only selection of pearlbush hardy for Minnesota. It can be pruned to a single trunk for a small tree, or grown as a shrub. Showy white flowers — two inches across — appear early in May.

'Honey Rose' honeysuckle flaunts showy pink flowers in late May.

'Northern Sun' forsythia is hardy to -30 degrees, and after winter its showy yellow flowers are a welcome April sight.